[Etiology, diagnosis and treatment of cicatricial tracheal stenosis]. / Etiologiya, diagnostika i lechenie rubtsovogo stenoza trakhei.

Development of tracheal surgery was associated with introduction of fundamentally new procedures: two-level reconstruction, redo tracheal resection, tracheal resection with simultaneous dissection of tracheoesophageal fistula. There are combined and staged techniques when tracheal repair or endoscopic interventions are performed as a stage before circular resection of trachea. However, a single algorithm for prevention and correction of postoperative complications is still absent in tracheal surgery. Further development of tracheal surgery directly depends on introduction of preventive measures and analysis of adverse factors associated with increased risk of complications. In this regard, ongoing researches in this area are very perspective.

[Contamination of surgical wound during tracheal resection depending on the mode of mechanical ventilation]. / Kontaminatsiya operatsionnoi rany v zavisimosti ot varianta IVL pri rezektsii trakhei.

OBJECTIVE: To analyze contamination of surgical wound during tracheal resection depending on the mode of mechanical ventilation. MATERIAL AND METHODS: There were 976 patients. Circular tracheal resection was made in 396 of these patients. RESULTS: Overall postoperative morbidity was 15.7%, mortality - 0.8%. Bacteriological examination of surgical wound was performed before tracheotomy and after formation of anastomosis depending on the method of mechanical ventilation. Surgical field was sterile before tracheotomy in all cases, contamination was confirmed after tracheotomy in all patients. Minimal contamination was observed in case of apneic oxygenation (100 times less than volumetric mechanical ventilation or high frequency mechanical ventilation). In all cases, several species of pathogenic microorganisms were identified. The number of species was also minimal in case of hypnotic mechanical ventilation. CONCLUSION: Contamination does not directly affect the development of local purulent-inflammatory process. However, this factor should not be ignored and compliance with all preventive measures is required.

[Tracheolaryngeal resection for cicatricle stenosis]. / Trakheogortannaia rezektsiia pri rubtsovom stenoze.

AIM: To determine the safest and the most effective surgical treatment of patients with cicatricle stenosis of tracheolaryngeal segment via analysis of different approaches. MATERIAL AND METHODS: For the period 1963-2015 at Petrovsky Russian Research Center for Surgery and Sechenov First Moscow State Medical University 1128 patients with cicatricle tracheal stenosis have been treated. There were 683 men and 445 women. 684 (60.6%) patients were young and the most employable (21-50 years). All patients were divided into 2 groups depending on time of treatment: the first one included 297 patients between 1963 and 2000, the second group - 831 patients between 2001 and 2015. In group 1 tracheolaryngeal anastomosis was made in 10 (16.9%) out of 59 patients who underwent tracheal resection. Previously indication for this surgery was cicatricle stenosis of cervical trachea and larynx with upper borderline of cicatricle changes at least 2 cm from vocal folds. In group 2 these procedures were more frequent. 94 (28.5%) out of 330 patients underwent tracheolaryngeal resection. Cranial borderline of lesion was within 0.5 cm from the vocal folds (only if posterior laryngeal wall at the level of cricoid cartilage was intact). Difficult patients are those who need for double-level or redo repair and procedures with tracheostomy. RESULTS: In the second group overall morbidity after tracheal resections followed by anastomosis was 5.6%. These complications were more common after tracheolaryngeal anastomosis (17%). There were no lethal outcomes after 94 tracheolaryngeal resections. Good long-term results were observed in 89.8% of patients after circular resection. Their quality of life was similar to that of healthy people. Preserved cicatricle tracheal segments during tracheal repair with T-shaped airway tube adversely affects quality of life in these patients in long-term period.

[POSTRESUSCITATION CICATRICIAL TRACHEAL STENOSIS. CURRENT STATE OF THE PROBLEM - THE SUCCESSES, THE HOPES AND DISAPPOINTMENTS.]

BACKGROUND: Currently, the trend continues to increase the number ofpatients with cicatricial tracheal stenosis (CTS). Therefore, prevention and treatment ofthis disease remains topical. The main cause ofcicatricial tracheal stenosis is damaging the trachea during mechanical ventilation. The scheme ofprevention of this disease in Russia hasn't brought the desired results. THE AIM: to clarify the modern etiology of cicatricial tracheal stenosis, to identify the trend in incidence rates, to determine whether there is an optimal safe alternative to tracheostomy including the use of minimally invasive techniques, to improve diagnostic and therapeutic algorithm at various stages of assistance, and also to study the results of innovative operations and new ways of maintaining gas exchange. MATERIALS AND METHODS: 1128 patients with cicatricial tracheal stenosis was treated from 1963 to 2015 in Petrovsky National Research Centre of Surgery and IMSechenov First Moscow State Medical University. Over time methods of di- agnosis, methods of anesthesia and operations have been varied. In this regard all patients were divided into two groups depending on the period of time from 1963 to 2000 (297 patients) andfrom 2001 to 2015 (831 patients). In recent decades there is a steady increase in the number of treated patients. So, if in the first group during the year operational treatment about the CTS 8,0 patients were underwent, in the second - to 55.4. Cicatricial tracheal stenosis appeared after lung mechanical ventilation at 1025 (for 90.9%) patients. They have undergone both radical one-stage treatment and multi-stage and sequential intraluminal procedures. In general there is a clear trend towards more aggressive surgical tactics. So, if in thefirst group, the tracheal resection with anastomosis was performedin 59 patients only, the second-330. Thefrequency ofpostoperative complications and mortality in the second group ofpatients was 12.9 and 0.7 %, respectively. RESULTS: Only a reasonable combination of all treatment methods, the principle of "every patient his own version of operation" allows to minimize the risk oftreatment and to get a good lasting result. Proof of such provision may be the fact that the frequency of complications and postoperative mortality at our patients have had a tendency to decrease and currently stands at 12.9 and 0.7 %, respectively for many years. It is 2.3 and 9.6 times less, respectively, than in the periodfrom 1963 to 2000. It appears that further reduction of these indicators will be at a slower pace, afurther solution of the CTS problem will be based on the prevention of disease. CONCLUSION: Prevention of cicatricial tracheal stenosis in the departments of reanimation and intensive care is currently inadequate. It requires fundamentally new approaches, but reform still has not brought the desired results. Diagnosis of the CTS at an early stage allows early treatment and to avoid complex and risky operations. Increasingly important, apart tracheoscopy for diagnosis of tracheomalacia purchase dynamic computed tomography and magnetic resonance - tomography. Treatment ofpatients with CTS requires a multidisciplinary approach, individual selection operations for a particular patient. The general trend of the further development of tracheal surgery is associated with an increase in the number of simultaneous resections, including at the long, two-level stenosis, as well as at relapse. The patients who had refused treatment or have elected him palliative options made possible surgery. The frequency of postoperative comnlications and mortality decreased significantiv, including after extensive and traumatic operations on the trachea.

Synergetic fMRI-EEG brain mapping in alpha-rhythm voluntary control mode.

For the first time in neurobiology-related issues, the synergistic spatial dynamics of EEG and fMRI (BOLD phenomenon) was studied during cognitive alpha biofeedback training in the operant conditioning mode (acoustic reinforcement of alpha-rhythm development and stability). Significant changes in alpha-rhythm intensity were found in T6 electrode area (Brodmann area 37). Brodmann areas related to solving alpha-training tasks and maximally involved in the formation of new neuronal network were middle and superior temporal gyri (areas 21, 22, and 37), fusiform gyrus, inferior frontal gyrus (areas 4, 6, and 46), anterior cingulate gyrus (areas 23 and 24), cuneus, and precuneus (area 7). Wide involvement of Brodmann areas is determined by psychological architecture of alpha-rhythm generating system control that includes complex cognitive activities: decision making, retrieval of long-term memory, evaluation of the reward and control efficiency during alpha-EEG biofeedback.

Quantum phenomena in ignition and detonation at elevated density.

The influence of quantum effects on the processes of initiation of combustion and detonation of hydrogen and acetylene near the low-temperature limits at elevated pressures is analyzed. A theoretical consideration which allows quantification of the quantum corrections to the rate constants of endothermic reactions associated with an increase in the high-energy tail of the equilibrium momentum distribution function at high pressures is presented. This quantum effect is caused by a manifestation of the principle of uncertainty for the energy of the colliding particles at a high frequency of collisions. It is shown that significant deviations of experimentally observed ignition and detonation delay time from the predictions of kinetic calculations are quite well described by the proposed quantum corrections. This general mechanism should be considered in the safety problem with emergency emissions of hydrogen at nuclear power stations, as well as problems of the safe production and storage of hydrogen and acetylene, which have a fundamental importance for industry and power engineering.

Communication: High speed optical investigations of a character of boiling-up onset.

In this communication, we discuss the phenomenon of attainable superheat of liquid and the peculiarities of its release by spontaneous boiling-up. We have combined the apparatus for superheating, namely, bubble chamber, with a high speed micro-optical method for detailed monitoring of the initial stage of boiling-up. In experiments on the isothermal pressure drop, it was found that the boiling-up onset of n-hexane is accompanied by characteristic step signal. The signal has proved to be typical of the heterogeneous character of boiling-up onset in a whole range of superheating degrees. The performance of the method for investigation of the refractive index and density for superheated liquids as functions of temperature and pressure has been revealed. The experimental error is estimated to be 0.1%.

[Clinical efficacy of the biospecific hemosorbent "Liposorb"].

The aim of the present work was to evaluate clinical efficacy of the biospecific hemosorbent "Liposorb". The main component of "Liposorb" is polyacrylamide gel containing an immobilized affine ligand (antibiotic polymyxin E-colistyne). 40 patients with abdominal sepsis and peritonitis of different genesis underwent a total of 52 seances of vein-venous extracorporeal hemoperfusion of hemosorbent "Liposorb". Endotoxin level (lipopolysaccharide - LPS) was measured by the turbodimetric method. Blood perfusion through a "Liposorb" column at 50-70 ml/min during 90 minutes permitted to reach stabilization of parameters of systemic hemodynamics. All the patients showed positive dynamics of general well-being, blood gas composition, clinical and biochemical blood analyses. The endotoxin (LPS) level of Gramm-negative flora significantly decreased. It is concluded that hemosorbtion using biospecific polymyxin-containing hemosorbent "Liposorb" effectively removes Gramm-negative endotoxin and leads to stabilization of hemodynamic in patients with Gramm-negative abdominal sepsis.

Engineering charge selectivity in alamethicin channels.

The peptide alamethicin provides a system for engineering ion channel charge selectivity. To define alamethicin charge selectivity experimentally, we measured single-channel current-voltage relationships in KCl gradients using covalently linked peptide dimers. Two factors were found to contribute to the charge selectivity of these channels: (i) the ionic strength of the surrounding solutions; and (ii) the distribution of fixed charge on the peptide. Native alamethicin channels exhibited either cation selectivity or anion selectivity depending on which end of the channel was at the low salt side of the membrane. When the glutamine residue at position 18 in the sequence was replaced with a lysine residue, an anion-selective channel was obtained regardless of which end of the channel was at the low salt side of the membrane.

Microwave tomography: two-dimensional system for biological imaging.

Microwave tomographic imaging is one of the new technologies which has the potential for important applications in medicine. Microwave tomographically reconstructed images may potentially provide information about the physiological state of tissue as well as the anatomical structure of an organ. A two-dimensional (2-D) prototype of a quasi real-time microwave tomographic system was constructed. It was utilized to reconstruct images of physiologically active biological tissues such as an explanted canine perfused heart. The tomographic system consisted of 64 special antennae, divided into 32 emitters and 32 receivers which were electronically scanned. The cylindrical microwave chamber had an internal diameter of 360 mm and was filled with various solutions, including deionized water. The system operated on a frequency of 2.45 GHz. The polarization of the incident electromagnetic field was linear in the vertical direction. Total acquisition time was less than 500 ms. Both accurate and approximation methods of image reconstruction were used. Images of 2-D phantoms, canine hearts, and beating canine hearts have been achieved. In the worst-case situation when the 2-D diffraction model was used for an attempt to "slice" three-dimensional (3-D) object reconstruction, we still achieved spatial resolution of 1 to 2 cm and contrast resolution of 5%.

Three-dimensional microwave tomography: experimental prototype of the system and vector born reconstruction method.

A method of image reconstruction in three-dimensional (3-D) microwave tomography in a weak dielectric contrast case has been developed. By utilizing only one component of the vector electromagnetic field this method allows successful reconstruction of images of 3-D mathematical phantoms. A prototype of the 3-D microwave tomographic system capable of imaging 3-D objects has been constructed. The system operates at a frequency of 2.36 GHz and utilizes a code-division technique. With dimensions of the cylindrical working chamber z = 40 cm and d = 60 cm, the system allows measurement of an attenuation up to 120 dB having signal-to-noise ratio about 30 dB. The direct problem solutions for different mathematical approaches were compared with an experimentally measured field distribution inside the working chamber. The tomographic system and the reconstruction method were tested in simple experimental imaging.

[Rhodopsin photo-oxidation: oxygen consumption and spectrum of activity]. / Fotookislenie rodopsina: raskhod kisloroda i spektr deistviia.

The coincidence of action spectrum of SH-groups and lipid oxidation is shown in the photoreceptor photodamaging process. Dose dependence of the process is measured in the maximum of photooxidation (380 nm). Dose of 0.1 J/cm2 is the threshold of photodamaging of photoreceptor membrane. Oxygen consumption in photooxidation of rhodopsin SH-groups and lipids are determined.

[The study of photo-induced rhodopsin aggregation in the photoreceptor membrane by electron paramagnetic resonance]. / Issledovanie svetoindutsirovannoi agregatsii rodopsina v fotoretseptornoi membrane metodom élektronnogo paramagnitnogo rezonansa.

The ESR measuring of UV-induced free radicals concentration limit has been used for studying rhodopsin aggregate state in the photoreceptor membrane.

[Mechanism of glutathione oxidation by photosensitized retinal]. / Mekhanizm fotosensibilizirovannogo retinalem okisleniia gliutationa.

Sulphur radicals appearing in the retinal photosensitized glutathione oxidation have been recorded by spin trapping. There is no reaction in the absence of oxygen. That is why the single oxygen is supposed to take part in the reaction (IId type photosensitized reaction).

[Retinal-sensitized photo-oxidation of rhodopsin]. / Sensibilizirovannoe retinalem fotookislenie rodopsina.

Kinetics of retinal photosensitized initiation of radicals of sulfhydryl groups of cysteine and rhodopsin is investigated by spin trapping. Photooxidation of both systems is the result of free radical mechanism. Photooxidation of SH-groups proceeds both with singlet oxygen participation and by direct interaction of photosensitizer with the substrate. The rate constants of these reactions are measured. The rate constant with oxygen participation (K0 = 1.1 X 10(9) M-1 S-1) is higher than the one without oxygen (K = 2.5 X 10(8) M-1 S-1) correspondingly. The lifetime of retinal triplet state in photoreceptor membrane is tau = 4 X 10(-6) s.